Well-casing spear.



W. Y. JACK.

WEL-L CASING SPEAR.

APPLICATAIUN FILED MAY16.1914.

2 SHEETS-SHEET l.

11,155,926. Patented 001;. 5, 1915.

| l l P W. Y. JACK.

WELL CASING SPEAR.

APPLICATION FILED MAYIG, 1914.

1,155,926., Patented oef. 5,1915.

` 2 SHEETS-SHEET 2.

l? gi M2M@ 'Wifim xfa 01.

UNITED STATES y WILLIAM .YATES JACK, 0F NEW YORK', 'I

WEIL-casina s-PEAB.

, of a plurality of dogs which are automaticlaims appended hereto.

cally retracted during the lowering of the tool into the well pipe andwhich automatically expand and grip-the pipe as the tool is aised,whereby the greater resistance of the casings removal the greater is thegrip of the dogs on the casing, so that slipping is V positivelyprevented. The invention has for its general objects to improve andsimplify thev construction of tools of the character referred to so asto be reliable and efficient in use, comparatively simple andinexpensive to manufacture, and so designed that the fishing for andremoval of a well pipe casing is greatly facilitated.

A further object of the inventionis the provision of a spear whichcomprises a head having longitudinally slidable dogs thereonwhich areconfined in dovetailed grooves that collectively converge upwardly sothat relative longitudinal movement of the head and dogs in onedirection will contract the dogs inwardly so that they can enter a wellpipe or be withdrawn, while Irelative longi-v tudinal movement in theopposite direction will expand or thrfow out the dogs so sto grip thewell pipe' or casing. 4

Another object of the invention isthe provision ofautomatic lockingmeans for lock ling the dogs in ,indrawn position so that the spear canbe released from and raised out of the well casing". l

With such objects in view, and others which will appear as thedescription proceeds, the invention comprises various novel features ofconstruction and arrangement of parts which will be set forth withparticularity in the following description and In the accompanyingdrawings, which illustrate certain embodiments of thev invention andwherein similar characters of 'reference indicate correspondinthefviews, Figure 1 is a side'view of the'well casing spear showing thesame gripping a `Speciiicatimu of Letters Patent.

Application filed Mayv 16, 1914. Serial No. 839,075.

Aparts in all Patented cees, 1915.-

well casing; Fig. 2 is a longitudinal section showing the. tool justabout to enter a well casing; Fig. 3 is a side view of the tool;showin'gvthe dogs in the act of releasing the pipe; Fig. 4 is anenlarged sectional view on the line 4-4, Fig. y2; Fig. 5 is an enlargedsectional view on the line 5-5,.Fig.`2; Fig.

6 `is a 'sectional view showing the dog-carrying rin locked in dogretracted or released position for permitting the tool' to be removedfrom the well casing; and Fig. .7 isa side view of a modified form ofthe tool.

vec i Referring .to the drawing, 1 designates the stem or shank ofthetool whichhas on its lower endl a longitudinally extending head2 formedwith a centeringpoint 3 at its lower end whereby the tool can bemorereadily entered into a lost well casing. This head is lprovided Yinits-surface with longitudinally extending grooves 4 of dove-tailedcross-section, as shown in Fig. 4,and in eachgroove is a longitudinallyslidable dog A5 which is of dove-tailed cross-section so that it willslide in its respective slot but w1ll be prevented from lateraldisplacement therefrom. The dove-tailed slots 4collectively convergeupwardly so that by `an upward movement of the head with respect to thedogs the latter will be expanded, whereas' a reverse movement will causea retraction or indrawing of the dogs, which actions are' necessaryrespectively for leasing the well casing.

A shoulder 6 .is provided at4v the end of the head2 `where i't joins theshank l1, and adapted to engage-this shoulder is al ring 7 freely:slidable onthe" shank 1, and

on this ring are suspended the dogs 5, which have their upper endsentered in a'chamber Y 8 in the ring and pivotally connectedvwithgripping 0r re.

the latter by studs 9 onthe dogs entering means may be employed forconnecting the dog to the ring in such a'manner as to provide for inwardand outward lateral movement of the dogs. As shown in Fig. 2, each doghas three portions 11, 12 and13 'contacting with the bottom of itsrespective apertures 1,0 in the wall of the chamber 8, although, ofcourse, any. other suitable groove 4, and as shown in Fig. 4, the.bot-'fv tom 14 o f each groove is cut on an arc whilei the portions ofcontact' of the dog are flat,-

lso that a very small arealofcontactis' rov A vided between each dog'and the head "o the 1. l o, tool. Thelower ends'of the dogs are bevlveled at 15 so as to freely enter the well casrllhe foregoingdescription applies to both forms of the tool and the'operation'now to Lbe explained will also apply to both of them. rlhe tool is suspended andlet down 7 intothewell by any suitable rigging, and

'during the downward travel of the tool the Adogs .will be expandedasshown in Fig. 2,.

vbecause the ring 7 will bev-resting on the shoulder 6. The point 3first enters the well Acasing C, Fig. 2,- and thereby guides the #toolinto the casing until the dogs are Yarrested by the gripping surfaces 16impinging on the upper edge of the casing, wherebythe dogs are arrestedin their downward movement while the head- 2 `continues to movedownwardly until a point is reached where the dogs are retractedinwardly @far and well pipe with it.

enoughV to drop .into the well casing. .An upward pull is now exerted onthe tool,

which results in the 'head upwardly while the dogs are forced out-Vwardly to cause their surfaces 16to grip the wellpipe, as clearly shownin Fig. 1, and after the tool is thus-"gripped to the well pipe, poweris appliedto draw up the tool 1t may be desirable in some instances toautomatically release the dogs from the well casing while thelatter isstill in the well. For this purpose ythe dog-,suspending ring isprovided with a 'plurality of springdisposed radially normally engagandin'this stem groove 19 at a point considerably above the upper end ofthe head, and consequently by .movlng the stem downwardly with respectthe well to the r1ng 7 a point is finally reached where the dogs willspring into the groove 19 and therebylock the ring 7 in a position wherethe dogs are completely indrawn or retracted. lrlhe relative movement ofthe head and dogs to lock the latter in retracted position is greaterthan the normal range of movement necessary to enable the dogs to enterpipeand to be thrown Vinto gripping engagement therewith, and to preventthe ring 7 under ordinary conditions from reaching. a point where thebolts snap into the annular recess 19, a helical spring 20 is placedaround the stem 1 with the lower end of the spring terminating somewhatbelow the shoulder V18, the upper end of the spring being engaged orconnected with a nut 21 screwed on the threaded portion 22 of the stem.By forcing the head and stem of thev tool downwardly, as by means of aheavy blow while the dogs are engaged with a well casing, thespring 20will be compressed by its contact with the ring and 'thereof moving-'Lieaeae the stem thereby moves more'than is ordinarily the case, sothat as a consequence the groove 19 will come opposite the springpressedbolt 17, the result being that the bolts snap into the groove 19 andthereby lock the ring 7 in raised position, whereby the dogs will beheld retracted. lin Fig. 3

bolts engage the shoulder 18, as clearly shown in Fig. 6, whereby thedogs are locked 'raised with respect to the head 2, so that the tool canbe removed from the well casing as shown in Fig. 3, the latter beingshown partly raised in this gre as compared with the position 'shown inFig. 2. rihe dog-releasing blow is' imparted by a collar 23 which freelyslides .on a guide sleeve 24 disposed around the threaded portion 22 ofthe stem and above the nut 21,

such collar being fastened to the lower end of a section of p ipe 25which forms part of the line by which the tool is suspended in loweringor raising. On the upper end of `the threaded portion 22 of the stem isprovided one or morev nuts 26 which engage the collar 23, whereby thetool is suspended. As a blow is to be imparted to the tool stem so 'asto retract the dogs and lock them retracted, the suspension line isallowed to drop very quickly, and in so doing the collar 23 will strikethe nut 21 and. impart a powerful blow thereto, whereby the tool stemand head will be forced downwardly while the dogs are engaged with thewell pipe, and hence relatively stationary, except that the dogs areretracted during this downward movement of the tool head, and finally apoint is reached where the springpressed bolt 17 engages the shoulder18, as shown in Fig. 6, when the tool can be raised out of the wellcasing. The locking bolts are provided with'handles 17a which projectthrough slots 7n in the ring 7, whereby the bolts can be retractedagainst the tension of their springs 17h, and the slots 7'a have offsets7b into which the handles can be turned to lock the bolts in retractedposition. When the bolts areall retracted the ring 7 slides downwardlyto the shoulder 6 of the tool body and then the bolts are again releasedso as toengage the stem 1, as shown in Fig. 2. i j

` From the foregoing 'description taken in connection with theaccompanying drawings Y the advantages of the construction and method ofoperation will be readily understood by those skilled in the art towhich the invention appertains, and while li have described the devicewhich l now consider to lbe the best embodiment thereof, ll desire tomerely illustrative and that such changes may be made when desired asare within the scope of the appended claims.

Having thus described my invention, I

claim as new and desire to secure by Letters Patent:

1...A well pipe 'spear comprising a head having in its surface aplurality of longitudinal dove-tailed grooves, dogs slidable in thegrooves and fitting the latter, and a supporting element on which thedogs are movably mounted and which is freely slidable axially of thetool, each groove and dog therein having contacting surfaces of whichone is convex and the other flat to provide longitudinal line contactsbetween the dogs and the head.

2. A well spear comprising a stem, a head on the stem, a dog slidablymounted on the head, a ring slidable on the stem and having a chamberedunder side into which the upper ends of the dogs extend, the surroundingwall of the chamber having apertures, and outwardly extending pins onthe upper ends of the dogs engaging in the openings for connecting thedogs with the ring.

3. A well casing spear comprising a stem, a head thereon, casinggripping jawson the head and slidable longitudinally thereof formovement laterally inwardly l and outwardly, a ring slidable onv thestem, said ring having its under side chambered to receive the upperends of the dogs, means for loosely connecting the dogs with. the wallof the chamber of the ring, whereby the dogs and ring move togetherlongitudinally of the head and stem, spring-pressed locking means on thering, and means on the stem with which the locking means engages whenthe ring is fully raised to support the dogs in retracted position.

parting a blow to the stem and head for moving the stem to a positionwhere the locking means engages the said means on the stem. v l l 5. Awell casing spear comprising a stem, a head, pipe gripping dogs on thehead and slidable longitudinally thereof to move the dogs inwardly andoutwardly, ay ring slidable on the stem and to which the dogs aremovably connected, spring-pressed bolts on the ring, a shoulder on thestem with which the bolts engage when the dogs are fully retracted, atool suspension and pull means including a collar free to slidedownwardly on the stem, an abutment on the stem to which the collarimparts a blow, and a yielding device on the stem for preventin the.said shoulder from reaching to the loc ing bolts of the ring eXcept\whenthe stem is moved downwardly by a blow imparted by the said collar.

' Y 6. A well casing spear comprising a stem,

a head, pipe gripping dogs on the head and slidable longitudmallythereof to move the dogs inwardly and outwardly, a ring slidable. on thestem and tol which the dogs are movably connected, spring-pressed boltson the ring, a shoulder on the stem with which the bolts engage when thedogs are fully retracted, a tool suspension and pull means thereof willengage ,the shoulder of the stem,V

except when the blow imparted to the Stem compresses the spring bythering engaging therewith and allowing the bolts to interlock withtheshoulder of the stem.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

WILLIAM YATES JACK.

Witnesses:

THOMAS C. CLIFF, CHARLES E. PFEIFFER'.

